Rockland County Solid Waste Management Authority

Each year, Rockland County is projected to realized the following savings from the SolarWall installations: Energy Savings: 1,475 MMBTU / year Heating Oil Displacement: 14,100 gallons / year CO2 Displacement: 165 tons / year At the time the project was approved in 2006, the cost of heating oil was $1.18 a gallon and the project had a payback period of under 10 years. As of 2008, the price of heating oil in NY state had tripled and was fluctuating in the range of $4 to $4.70 a gallon, resulting in a 3 year payback. Given the magnitude of the energy reductions, this highlights why the SolarWall technology offers such a compelling ROI in terms of hedging against volatile energy prices

Background

The Rockland County Solid Waste Management Authority
administers and treats the solid waste from wastewater
that is generated within the county. The co-composting
facility is one of the buildings that they administer, and in
2005, Dvirka & Bartilucci (D&B) Consulting Engineers
were tasked with overseeing a series of process, structural,
and energy efficiency improvements.

Solution

As part of the energy efficiency improvements, D&B Engineers
investigated commercially available solar heating
systems to offset the large quantities of energy required in
the waste drying application. They recommended the
SolarWall® technology, which is ideally suited to commercial
process drying applications.
SolarWall® systems were installed on the southeast and
southwest walls to provide heat to two 3-million BTU/hr
oil-fired heating systems. The overall project was divided
into three systems, and is summarized below.
SolarWall® System One: 1,265 ft2
(118 m2
) of panels were
installed on the southeast wall. 11,000 cfm air is preheated
and connected to the oil heater on the northeast
corner of the facility;
SolarWall® System Two: The solar collector area is 3,815
ft2
(355 m2
) on the southeast facing wall. 17,500 cfm of
air is preheated and delivered to the second oil heater on
the southwest corner;
SolarWall® System Three: Covers 2,900 ft2
(270 m2
) on
the southwest wall. Designed for preheating 17,500 cfm
of air, which is also connected to the second oil heater.